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HMRC internal manual

Trusts, Settlements and Estates Manual

Legal background to trusts and estates: Scottish law: further reading

If you want further reading, try the following

Scots law (general)  
General Principles of Scots Law Marshall
Introduction to the Law of Scotland Gloag & Henderson
Trust law  
Trusts, Trustees and Executors Wilson & Duncan
Trusts Norrie & Scobbie
Scots terminology  
Students’ Glossary of Scottish Legal Terms Green